The present invention relates to methods and apparatus for filling "bone dry" batteries with electrolyte which includes an acid. The batteries are the type that may be used for example in automobiles, garden tractors or mowers and motorcycles. In one typical situation in industry, a dealer in garden tractors will receive new tractors with the batteries in a "bone dry" state. The dealer must fill the batteries with an acid electrolyte. However, experience has shown that present methods and apparatus for supplying acid electrolyte to the batteries usually results in over-filling at least two or more battery cells. In addition to harmful contact with the user, the spilled acid electrolyte may contact the battery or the floor requiring immediate clean-up of the acid to prevent its corrosive effects. In situations where the spilled acid contacts the brand new lawn mower or tractor, the paint will be removed requiring that the mower or tractor be returned to the manufacturer thereby increasing expense.
After filling the battery with acid, the remaining acid in conventional containers must be disposed of such as by first neutralizing the acid with a base, for example, baking soda and then dumping the neutralized substance in an area approved by pollution standards.
One typical method presently used in industry includes the provision of a squeezeable plastic container including the acid electrolyte and provided with a clear squeezeable plastic tube whose one end is inserted in the container through a cap at the top of the container. The other end of the tube is inserted into a cell of the battery and the container is squeezed with one hand to force the acid through the tube and into the container. The other hand is used to squeeze the tube to stop the flow of acid into the battery cell at the precise moment when the cell is full. The process must be repeated for each of the six cells of a typical battery.
However, experience has shown that it is difficult if not impossible to fill the first two or three battery cells in the above manner without spillage of the acid. For this reason a conventional acid pack for a battery requiring seventy-seven ounces of electrolyte will contain about eighty ounces of electrolyte to compensate for the spilled electrolyte. In many cases, the acid pack will still have some acid remaining after use thus requiring the added precaution of properly disposing of the acid.
Another method of the prior art utilizes a plurality of individual containers blow molded together with each container having a sealed outlet at one end and a sealed vent at the other end. The container outlets are first cut to open them and then the containers are simultaneously inserted into the battery. The vents of each container are then cut to open their interiors to atmosphere whereupon the electrolyte will flow into the battery cells. Such an assemblage of containers is not only expensive to manufacture but it also requires that each container be individually charged with electrolyte during the manufacturing process and further requires that each of the container vents be individually cut or opened to allow dispensing of the electrolyte. Containers of this general type are disclosed in U.S. Pat. Nos. 4,565,750 and 4,833,047 to Isoi et al.